Alternative diagnosis to heparin-induced thrombocytopenia in two critically ill patients despite a positive PF4/heparin-antibody test. (November 2013)

• Record Type: Journal Article
• Authors: Hron, Gregor; Knutson, Folke; Thiele, Thomas; Althaus, Karina; Busemann, Christoph; Friesecke, Sigrun; Greinacher, Andreas; Lubenow, Norbert
• Is Part Of: Upsala journal of medical sciences. Volume 118:Number 4(2013:Dec.)
• Page Start: 279
• Page End: 284
• Publication Date: 2013-11
• Subjects: Medicine -- Periodicals; Medicine -- Periodicals; Electronic journals; 610.5
• DOI: 10.3109/03009734.2013.838811
• Languages: English
• ISSNs: 0300-9734

Abstract

<abstract> <title>Abstract</title> <p>Thrombocytopenia can cause diagnostic challenges in patients who have received heparin. Heparin-induced thrombocytopenia (HIT) is often considered in the differential diagnosis, and a positive screening can be mistaken as confirmation of the disorder. We present two patients who both received low-molecular-weight heparin for several days. In the first patient, clinical judgment rejected the suspicion of HIT despite a positive screening assay, and treatment for the alternative diagnosis of post-transfusion purpura was correctly initiated. In the second patient, the inaccurate diagnosis HIT was pursued due to a positive screening assay, while the alternative diagnosis of drug-dependent thrombocytopenia caused by piperacillin/tazobactam was rejected. This resulted in re-exposure to piperacillin/tazobactam which caused a second episode of severe thrombocytopenia. A positive screening assay for platelet factor 4/heparin-antibody should be verified by a functional assay, especially in patients with low pretest probability for HIT.</p> </abstract>